Injection of medication often requires that a liquid drug be drawn from a vial or ampoule containing the medication into a syringe or cartridge prior to delivery of the liquid via a needle to the target. The needle serves as both the element that punctures the medication vial to permit reconstitution and withdrawal of drug and the element that punctures the target tissue for delivery. FIGS. 1A-E are schematics of a typical liquid drug extraction method using a needle and syringe.
As shown in FIGS. 1A-E, the common method used to fill a syringe involves inserting the syringe needle into the vial through a self-sealing septum (FIG. 1A), inverting the vial (FIG. 1B), and pushing a volume of air equivalent to the desired volume of drug into the vial (FIG. 1C). When the syringe piston is drawn back, as illustrated in FIG. 1D, the syringe is filled with liquid from the vial, except a small volume of air remaining in the syringe because of dead space in the needle itself is then removed as shown in FIG. 1E. While this procedure is common practice for filling a syringe, modern needle-free injection devices do not use needles. As such, there is no needle to pierce the rubber septum sealing the vial and there exists a need for an adaptor that enables removal of liquid from a vial using a needle-free syringe.